<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package    CodeIgniter
 * @author    EllisLab Dev Team
 * @copyright    Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
 * @copyright    Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
 * @license    http://opensource.org/licenses/MIT    MIT License
 * @link    http://codeigniter.com
 * @since    Version 3.0.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * CodeIgniter Session Driver Class
 *
 * @package    CodeIgniter
 * @subpackage    Libraries
 * @category    Sessions
 * @author    Andrey Andreev
 * @link    http://codeigniter.com/user_guide/libraries/sessions.html
 */
abstract class CI_Session_driver implements SessionHandlerInterface {

    protected $_config;

    /**
     * Data fingerprint
     *
     * @var    bool
     */
    protected $_fingerprint;

    /**
     * Lock placeholder
     *
     * @var    mixed
     */
    protected $_lock = FALSE;

    /**
     * Read session ID
     *
     * Used to detect session_regenerate_id() calls because PHP only calls
     * write() after regenerating the ID.
     *
     * @var    string
     */
    protected $_session_id;

    // ------------------------------------------------------------------------

    /**
     * Class constructor
     *
     * @param    array    $params    Configuration parameters
     * @return    void
     */
    public function __construct(&$params)
    {
        $this->_config =& $params;
    }

    // ------------------------------------------------------------------------

    /**
     * Cookie destroy
     *
     * Internal method to force removal of a cookie by the client
     * when session_destroy() is called.
     *
     * @return    bool
     */
    protected function _cookie_destroy()
    {
        return setcookie(
            $this->_config['cookie_name'],
            NULL,
            1,
            $this->_config['cookie_path'],
            $this->_config['cookie_domain'],
            $this->_config['cookie_secure'],
            TRUE
        );
    }

    // ------------------------------------------------------------------------

    /**
     * Get lock
     *
     * A dummy method allowing drivers with no locking functionality
     * (databases other than PostgreSQL and MySQL) to act as if they
     * do acquire a lock.
     *
     * @param    string    $session_id
     * @return    bool
     */
    protected function _get_lock($session_id)
    {
        $this->_lock = TRUE;
        return TRUE;
    }

    // ------------------------------------------------------------------------

    /**
     * Release lock
     *
     * @return    bool
     */
    protected function _release_lock()
    {
        if ($this->_lock)
        {
            $this->_lock = FALSE;
        }

        return TRUE;
    }

}
